Method for manufacturing tape tab fasteners

ABSTRACT

A method for the manufacture of tape tab stock that may be used to produce tape tabs for use with disposable absorbent articles, as well as a method for the on-line manufacture of tape tabs that may be manufactured concurrently with the chassis of the absorbent article to which the tape tabs will be attached. The first step is to provide a backing substrate upon which the adhesives of the tape tab can be applied. Once the backing is provided, a pressure-sensitive adhesive is applied to regions of one side of the backing substrate. (The pressure-sensitive adhesive preferably functions as the adhesive used to fasten an element of the absorbent article, such as a front waist region, to another element of the absorbent article, such as a rear waist region.) The backing substrate is then slit in a direction parallel to the machine direction and the release surface of a release substrate is placed in contact with the pressure-sensitive adhesive, forming a laminate comprising the backing substrate and the release substrate. The release substrate preferably covers the entire surface of the backing substrate upon which pressure-sensitive adhesive has been applied. However, in a preferred embodiment, at least a portion of the backing substrate extends outwardly in a direction parallel to the cross machine direction beyond the longitudinal edges of the release substrate. The surface of the laminate, including the surface of the release substrate that is not in contact with the pressure-sensitive adhesive, and any of the backing substrate not covered by the release substrate is then coated with a construction adhesive. (The construction adhesive is used to join the tape tabs to the absorbent article.) After the construction adhesive is applied to the surface of the laminate, the laminate is slit in a direction parallel to the machine direction and either rewound for shipping or storage, or fed to a taper unit that is integrated into the absorbent article manufacturing line. The taper unit cuts individual tape tabs and applies them to the absorbent article chassis.

This application is a continuation-in-part of application Ser. No.08/263,322, filed on Jun. 21, 1994, now U.S. Pat. No. 5,482,588; and acontinuation-in-part of application Ser. No. 08/263,115, filed on Jun.21, 1994, now U.S. Pat. No. 5,487,809.

FIELD OF THE INVENTION

The present invention relates to a method for manufacturing tape tabstock that may be used to produce tape tabs for use with disposableabsorbent articles comprising tape tab closure members, and a method formanufacturing tape tab stock that can be produced on-line andconcurrently with the disposable absorbent articles to which the tapetabs are to be joined.

BACKGROUND OF THE INVENTION

Disposable absorbent articles, such as diapers, training pants,incontinence garments, feminine hygiene garments and the like havebecome very popular in the market place today. Typically, adhesive tapetabs fasteners are used to secure the absorbent articles about the waistof the wearer. Such fasteners are generally manufactured separately fromthe absorbent articles to which they are attached. For example, it iscommon for the manufacture of tape tabs to take place in differentfacilities than the manufacture of the absorbent article chassis, and ata different time. Generally, tape tabs are manufactured by applying arelease agent to a backing and winding the backing onto a roll. The rollof backing material treated with a release agent is then unwound andcoated with pressure-sensitive adhesive, forming a tape stock. The tapestock is then rewound onto rolls for shipping. Finally, at the place ofmanufacture of the absorbent article, the tape stock is unwound, cut tosize, and joined to the chassis of an absorbent article.

An overriding consideration in the construction of a disposableabsorbent article is the cost of manufacturing the absorbent article.The present invention provides a reduced cost method for the manufactureof tape tabs for use with disposable absorbent articles. If desired, thetape tabs can be manufactured concurrently with the chassis of theabsorbent articles and in the same location, thus eliminating the needto rewind the tape stock or prepare it for shipping. This alsoeliminates the need to coat the non-adhesive surface of the tape stockwith a release agent, simplifying the process of manufacturing the tapetabs and reducing the overall cost of manufacturing the disposableabsorbent articles.

It is an object of the present invention to provide a low cost methodfor manufacturing tape tab stock that may be used to produce tape tabsfor use with disposable absorbent articles.

It is a further object of the present invention to provide a method forthe on-line manufacture of tape tabs to be used with disposableabsorbent articles.

It is yet another object of the present invention to provide a methodfor the manufacture of tape tabs and tape tab stock with improvedprocessibility and hygiene.

These and other objectives of the present invention will be more readilyapparent when considered in reference to the following description andwhen taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

The present invention provides a method for the manufacture of tape tabstock that may be used to produce tape tabs for use with disposableabsorbent articles, as well as a method for the on-line manufacture oftape tabs that may be manufactured concurrently with the chassis of theabsorbent article to which the tape tabs will be attached. The firststep is to provide a backing substrate upon which the adhesives of thetape tab can be applied. Once the backing is provided, apressure-sensitive adhesive is applied to regions of one side of thebacking substrate. Preferably, the pressure-sensitive adhesive isapplied in zones that are located transversely inwardly from thelongitudinal edges of the backing substrate at least 0.5 mm. It is alsopreferred that the pressure-sensitive adhesive zones be separated aboutthe longitudinal centerline forming an area free of adhesive at least0.5 mm in width. (The pressure-sensitive adhesive preferably functionsas the adhesive used to fasten an element of the absorbent article, suchas a front waist region, to another element of the absorbent article,such as a rear waist region.) The backing substrate is then slit in adirection parallel to the machine direction and the release surface of arelease substrate is placed in contact with the pressure-sensitiveadhesive, forming a laminate comprising the backing substrate and therelease substrate. The release substrate preferably covers the entiresurface of the backing substrate upon which pressure-sensitive adhesivehas been applied. However, in a preferred embodiment, at least a portionof the backing substrate extends outwardly in a direction parallel tothe cross machine direction beyond the longitudinal edges of the releasesubstrate. The surface of the laminate, including the surface of therelease substrate that is not in contact with the pressure-sensitiveadhesive, and any of the backing substrate not covered by the releasesubstrate is then coated with a construction adhesive. In a preferredembodiment, the construction adhesive is applied such that there areareas free of construction adhesive of at least 0.5 mm in width alongthe longitudinal edges of the release substrate and about thelongitudinal centerline of the laminate. (The construction adhesive isused to join the tape tabs to the absorbent article.) After theconstruction adhesive is applied to the surface of the laminate, thelaminate is slit in a direction parallel to the machine direction andeither rewound for shipping or storage, or fed to a taper unit that isintegrated into the absorbent article manufacturing line. The taper unitcuts individual tape tabs and applies them to the absorbent articlechassis.

The present invention provides a low cost method for manufacturing tapetab stock that may be used to produce tape tabs for use with absorbentarticles. The method of the present invention eliminates the need toapply a release agent to the surface of the backing substrate to whichno adhesive is applied. Further, the method of the present invention canbe performed concurrently with the manufacture of the absorbent articleto which the tape tabs are to be attached, thus, eliminating the need torewind the tape stock. Therefore, a simplified and more economicalprocess is provided for manufacturing tape tabs for use with disposableabsorbent articles.

An alternative embodiment of the present invention provides a method forthe manufacture of a one-piece tape tab. As above, a backing substrateis provided and a pressure-sensitive adhesive is applied to one surfaceof the backing substrate. The backing substrate is then slit in adirection parallel to the machine direction. However, rather thanutilizing a separate release substrate to form a release surface for thepressure-sensitive adhesive of the tape tabs, the backing substratecomprises an integral release surface to which the pressure-sensitiveadhesive of the tape tab may be releasably fastened.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter which is regarded as thepresent invention, it is believed that the invention will be betterunderstood from the following description which is taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a plan view of an absorbent article comprising a tape tabmanufactured by on-line process.

FIG. 2 is a representative side view of the process for on-linemanufacturing tape tabs for use with absorbent articles.

FIGS. 3a-3f represent a plan view of the process for on-linemanufacturing tape tabs for use with absorbent articles, showing theflow of the process in the machine direction.

FIG. 4 is a cross-sectional view of the laminate shown in FIG. 3e.

FIG. 5 is cross-sectional view of a two-piece tape tab produced by themethod of the present invention.

FIG. 6 is a cross-sectional view of the laminate that forms theone-piece tape tab embodiment produced by the method of the presentinvention.

FIG. 7 is a plan view of a portion of an absorbent article comprising aone-piece tape tab embodiment produced by the method of the presentinvention.

FIG. 8 is cross-sectional view of a preferred embodiment of thetwo-piece tape tab produced by the method of the present invention.

FIG. 9 is cross-sectional view of a preferred embodiment of thetwo-piece tape tab produced by the method of the present invention.

FIG. 10 is cross-sectional view of an alternative preferred embodimentof the two-piece tape tab produced by the method of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

The method of the present invention is particularly suitable formanufacturing tape tabs for use with disposable absorbent articles. Asused herein, the term "absorbent article" refers to devices which absorband contain body exudates, and more specifically, refers to deviceswhich are placed against the skin of a wearer to absorb and contain thevarious exudates discharged from the body. The term "disposable" is usedherein to describe absorbent articles which are not intended to belaundered or otherwise restored or reused as an absorbent article aftera single use (i.e. they are intended to be discarded, and preferably,recycled, composted or otherwise disposed of in an environmentallycompatible manner). A "unitary" absorbent article refers to an absorbentarticle which is formed from separate parts united together to form acoordinated entity so that they do not require separate manipulativeparts like a separate holder and liner. A preferred embodiment of aunitary absorbent article comprising tape tabs manufactured by themethod of the present invention is the disposable absorbent articleshown in FIG. 1. As used herein, the term "diaper" refers to anabsorbent article generally worn by infants and incontinent persons thatis generally worn about the lower torso of the wearer. It should beunderstood, however, that the present invention is also applicable toother absorbent articles such as incontinence briefs, diaper holders,feminine hygiene garments, training pants, and the like.

With reference to FIG. 1, an absorbent article, such as diaper 20,generally comprises a liquid permeable topsheet 22, a liquid impermeablebacksheet 24, and an absorbent core 26 sandwiched between the topsheet22 and the backsheet 24. The diaper 20 preferably further comprises afront waist region 36, a rear waist region 38, elasticized leg cuffs 28,ear flaps 30, an elastic waist feature 32 and a fastening system 34comprising at least one tape tab 40. An example of a preferred absorbentarticle to which the tape tabs of the present invention may be joined ismore fully and completely described in U.S. Pat. No. 5,151,092 entitled"Absorbent Article With Dynamic Elastic Waist Feature Having APredisposed Resilient Flexural Hinge", issued to Buell et al. on Sep.29, 1992 which is hereby incorporated by reference herein.

One preferred tape tab produced by the method of the present inventionis shown in FIGS. 8 and 9. The tape tab 40 comprises a backing substrate52 comprising at least one construction adhesive 56 and onepressure-sensitive adhesive 54. (However, it should be noted that theconstruction adhesive 56 may comprise a pressure-sensitive adhesive.)The construction adhesive 56 is attached to the backsheet 24 and isseparated from the pressure-sensitive adhesive 54 a distance greaterthan or equal to about 0.5 mm. The construction adhesive 56 is spacedinwardly from the backing substrate 52 edge 201 by a distance greaterthan or equal to about 0.5 mm. The pressure-sensitive adhesive 54 isspaced inwardly from the backing substrate edge 83 by a distance ofgreater than or equal about 0.5 mm. A release substrate 50 is attachedto the topsheet 22 by a permanent adhesive 56 which ends at a distancegreater than or equal to about 0.5 mm from edge 203 of the releasesubstrate 50. In another preferred execution the permanent adhesive 56also ends at a distance greater than or equal to about 0.5 mm from edge202 of the release substrate.

An alternative preferred adhesive tape tab 40 is shown in FIG. 10. Thetape tab 40 comprises a backing substrate 52 comprising a singlepressure-sensitive adhesive 54. The pressure-sensitive adhesive 54serves to join the backing substrate 52 to the backsheet 24 as well asprovide a surface which may be used for fastening. Thepressure-sensitive adhesive 54 is preferably inwardly positioned fromedges 83 and 201 of the backing substrate 52 by a distance greater thanor equal to about 0.5 mm. The release substrate 50 is preferably joinedto the topsheet 22 with a construction adhesive as described with regardto the tape tab of FIGS. 8 and 9.

Overall method of on-line manufacture of tape tabs

The tape tabs 40 of the present invention are made by first providing abacking substrate upon which the adhesives of the tape tab 40 can beapplied. A pressure-sensitive adhesive is applied to regions of one sideof the backing substrate. (As described above, the pressure-sensitiveadhesive preferably functions as the adhesive used to fasten an elementof the absorbent article, such as the front waist region 36, to anotherelement of the absorbent article, such as the rear waist region 38.) Thebacking substrate is then preferably slit in a direction parallel to themachine direction and a release substrate is placed in contact with thepressure-sensitive adhesive, forming a laminate comprising the backingsubstrate, the pressure-sensitive adhesive and the release substrate.The surface of the laminate, including the surface of the releasesubstrate, as well as any portion of the backing substrate not coveredby the release substrate is then coated with a construction adhesive forjoining the tape tabs to the absorbent article. After the constructionadhesive is applied to the surface of the laminate, the laminate ispreferably slit in a direction parallel to the machine direction and fedto a taper unit that is integrated into the absorbent articlemanufacturing line. The taper unit cuts individual tape tabs 40 from thelaminate and joins the tape tabs 40 to the chassis of the absorbentarticles. This process is illustrated in FIGS. 2 and 3.

The tape tabs 40 of the present invention may be produced on theapparatus 100, as shown in FIG. 2. The apparatus 100 comprises twoseparate process modules, process module 110 for providing a releasesubstrate 50; and process module 112 for providing a backing substrate(or "backing") 52, applying a pressure-sensitive adhesive 54 to thebacking 52 and slitting the backing 52 prior to contacting the releasesubstrate 50 to the pressure-sensitive adhesive 54 disposed on thebacking 52. In a preferred embodiment, the apparatus 100 is integratedinto a disposable absorbent article manufacturing line such that thetape tabs 40 of the present invention are manufactured "on-line". (Asused herein, the term "integrated" means interconnected process modulesthat operate concurrently to produce finished products from sourcematerials. The term "on-line" is used to refer to the process ofmanufacturing the tape tabs 40 of the present invention on an apparatusthat is integrated with the manufacturing line that produces thedisposable absorbent articles to which the tape tabs will be joined.)

The backing substrate

Examining process module 112 in greater detail, a backing substrate 52is provided and taken from the unwind roll 120. The backing substrate 52may comprise any material to which a pressure-sensitive adhesive and apermanent adhesive, such as a hot melt adhesive, may be applied. Somenonlimiting examples of suitable backing substrates include films,laminates, woven and nonwoven webs, foams, and the like. In a preferredembodiment, the backing substrate 52 comprises a cellulose, polyolefinor polyester film ranging in thickness from about 2.5 mils to about 5.0mils in thickness, more preferably about 4 mils in thickness. Apolyolefin film that has been found to be particularly suitable for thebacking substrate is the polypropylene film manufactured by the ExxonChemical Company of Lake Zurich, Ill., under the trade name EX-377. Acellulose film that has been found to be suitable is manufactured by theKimberly-Clark Corporation of Dallas, Tex. under the trade name C-49490.

As shown in FIG. 2, the backing substrate 52 is taken from the unwindroll 120 and passes through the S-wrap tensioning rolls 124 to provideproper tensioning and to prevent puckering or bunching of the backing52. If necessary, a tracking system (not shown) as is commonly utilizedand known in the art, may be employed in the process module 112 tooptimally track and adjust the backing substrate 52 into the S-wraptensioning rolls 124. A tracking system manufactured by the FifeCorporation of Oklahoma City, Okla., and sold as Model Op6 LRA may besuitable.

Guide roll 126 guides the backing 52 into position adjacent the adhesiveslot coater 130 for application of the pressure-sensitive adhesive 54.The adhesive slot coater 130 may be any adhesive slot coater as is knownin the art. Similarly, the pressure-sensitive adhesive 54 may be anypressure-sensitive adhesive as is known in the art, including, but notlimited to pressure-sensitive adhesives, cohesives, solvent basedadhesives or water based adhesives. Some examples of preferredpressure-sensitive adhesives include the pressure-sensitive adhesivesHL-1414 and HL-1350 manufactured by the H. B. Fuller Company of St.Paul, Minn.; and H-2153 manufactured by the Findley Adhesive Corporationof Wauwatosa, Wis. The adhesive slot coater 130 preferably applies thepressure-sensitive adhesive 54 to the backing 52 in a heated, liquidstate. The slot coater 130 preferably applies the adhesive 54 to thebacking 52 such that adhesive free gaps 74, 75, and 76 are present.These gaps are preferably greater than or equal to about 0.5 mm to aidin processibility (i.e., slitting, if required) and process hygiene.After the pressure-sensitive adhesive 54 is applied, the backing 52 ispreferably directed to a chill roll 132 such that the pressure-sensitiveadhesive 54 is cooled and permitted to solidify on the surface of thebacking 52.

Once the pressure-sensitive adhesive 54 has been applied, and preferablycooled, the backing 52 is preferably directed to a shear slittingapparatus 134 that slits the backing 52 in a direction parallel to themachine direction. The slitting operation preferably slits this backing52 parallel to the machine direction within the adhesive free area 75.(It should be noted, however, in less preferred embodiments, the backing52 is not slit and separated. In such embodiments, a single piece oftape tab stock 70 results rather than the multiple segments as describedmore fully below with regard to the preferred embodiments.) The backing52 is then separated laterally at the slit. (As used herein, the term"laterally" is defined as the direction perpendicular to the machinedirection, or parallel to the cross machine direction.) The backing 52may be separated by any means as are known in the art, including but notlimited to any web spreader 136 as is known in the art.

The release substrate

The backing 52 comprising the pressure-sensitive adhesive 54 is directedto a nip between the combining rolls 140 where the surface of thebacking 52 comprising the pressure-sensitive adhesive 54 is placed incontact with the release surface of a release substrate 50. The releasesubstrate 50 generally comprises a base material and a release agentdisposed on at least one surface of the base material. However, releasesubstrates are available wherein the base material itself acts as arelease agent, and thus, no other release agent is needed. The releaseagent may be applied to the base material "on-line", or premanufacturedas shown in FIG. 2. The base material of the release substrate 50 may beany material as is known in the art, including, but not limited tofilms, laminates, woven and nonwoven webs, foams, and the like. Examplesof suitable base materials for the release substrates of the presentinvention comprise cellulose materials or polypropylene films, rangingin thickness from 1.0 to 5.0 mils. One preferred base material for therelease substrate 50 is the polypropylene film EX-399 manufactured bythe Exxon Chemical Company of Lake Zurich, Ill. Another preferred basematerial for the release substrate 50 is the cellulose film 1224212manufactured by the Rhinelander Paper Company of Rhinelander, Wis. Therelease agent may be any release agent as is known in the art that willact as a release agent for the particular pressure-sensitive adhesive 54utilized. An example of a suitable release agent that works well withmany different base materials and pressure-sensitive adhesives issilicone. The Goldschmidt Company of Essen, West Germany manufacturessilicone formulas that can be used as release agents under the tradenames RC711 or RC726. (In preferred embodiments, the release agentcomprises a mixture of the RC711 and RC726 silicone formulas.)

As shown in FIG. 2, the release substrate 50 is taken from the unwindroll 122 and passes through the S-wrap tensioning rolls 138 to provideproper tensioning and to prevent puckering or bunching of the releasesubstrate 50. If necessary, a tracking system (not shown) as is commonlyutilized and known in the art, may be employed in the process module 110to optimally track and adjust the release substrate 50 into the S-wraptensioning rolls. As with the process module 112, a tracking systemmanufactured by the Fife Corporation of Oklahoma City, Okla., and soldas Model Op6 LRA may be suitable to ensure proper tracking of therelease substrate 50 in the process module 110.

Joining the backing substrate with the release substrate

The surface of the backing substrate 52 comprising thepressure-sensitive adhesive 54 is contacted with the surface of therelease substrate 50 comprising the release agent as the substrates passthrough the nip between the combining rolls 140. The backing substrate52 and the release substrate 50 become releasably joined together,forming a laminate 60. The laminate 60 is directed to pass adjacent anadhesive spray nozzle 150 where a construction adhesive 56 is applied tothe surface of the release substrate 50, forming a tape tab stock 70.The spray nozzle 150 may be any adhesive spray nozzle known in the art,including, but not limited to a J&M meltblown nozzle available from J&MLaboratories, Inc. of Dawsonville, Ga. or a Nordson spiral nozzleavailable from the Nordson Corporation of Norcross, Ga. The constructionadhesive 56 may comprise any adhesive or combination of adhesives knownin the art, including, but not limited to, pressure-sensitive adhesives,cohesives, solvent based adhesives or water based adhesives. Preferably,however, the construction adhesive 56 is preferably a permanent hot meltadhesive. One such adhesive is the hot melt adhesive HL-1358,manufactured by the H. B. Fuller Company of St. Paul, Minn. Theconstruction adhesive 56 may be applied in any pattern as is known inthe art, including but not limited to lines, dots, spirals or agenerally continuous layer of adhesive. In one preferred embodiment, thewidth of adhesive 56 is applied such that there is an adhesive free areaof greater than or equal to about 0.5 mm from the side edge 100 of therelease substrate 50. It is also preferred to have an adhesive free area101 parallel to the longitudinal centerline L of greater than or equalto about 0.5 mm. This aids processibility and hygiene in embodimentswherein the tape tab stock 70 is slit along the longitudinal centerlineL.

After the construction adhesive 56 is applied to the tape tab stock 70,the tape tab stock 70 is preferably directed to a second shear slitter160 where the tape tab stock 70 is slit in a direction parallel tomachine direction. The tape tab stock 70 is then separated at the slitby a tape tab stock spreader 162 and fed directly into a standard taperunit 170 as is commonly known in the art. One suitable taper unit, assupplied by Curt G. Joa, Inc of Sheboygan Falls, Wis., feeds the tapetab stock 70 to a vacuum anvil roll where the tape tab stock 70 is cutinto individual tape tabs 40, spaced apart (slipped) and joined to theabsorbent article.

Alternatively, the tape tab stock 70 may be rewound for storage orshipment and later fed into a taper unit on an absorbent articlemanufacturing line. If rewinding of the tape tab stock 70 is desired, itis preferred that the construction adhesive 56 have the ability to loseits adhesive properties during the period in which the tape tab stock 70is wound and yet be able to reactivated upon demand at a later time. (Asused herein, the term "reactivated" refers to the ability of an adhesivethat has lost its adhesive properties to regain its adhesive propertiesat a later time.) Some nonlimiting examples of adhesives that have theability to lose their adhesive properties and to be reactivated at alater time include hot melt adhesives, water activated adhesives,radiation activated adhesives and ultra-violet light activatedadhesives.

Preferred Embodiments

a. Two-piece tape tab

One preferred embodiment of the present invention for manufacturing atwo-piece tape tab is depicted in FIGS. 3a-3f. As shown in FIG. 3a, abacking substrate 52, as described above, is provided having alongitudinal centerline L and a transverse centerline T perpendicular tothe longitudinal centerline L. (As used herein, the term "longitudinalcenterline" refers to an imaginary line that runs parallel to themachine direction. The "transverse centerline" runs perpendicular to themachine direction and parallel to the cross machine direction.) Thebacking substrate 52 further comprises a first surface 80, a secondsurface 82 opposed to the first surface 80, and a pair of outerlongitudinal edges 84. (As shown in FIG. 3c, the backing substrate 52further comprises a pair of inner longitudinal edges 83 once the backingsubstrate has been slit.)

FIG. 3b shows a plan view of the backing substrate 52 after it haspassed the slot coater 130, having the pressure-sensitive adhesive 54applied to the first surface 80. In a preferred embodiment, thepressure-sensitive adhesive 54 is not applied to the entire firstsurface 80 of the backing substrate 52. Rather, it is preferred that thepressure-sensitive adhesive 54 be applied continuously to the backingsubstrate 52 in zones, preferably at least a first zone 86 and a secondzone 88. (As used herein, the term "continuously" means a generallyunbroken pattern.) The first zone 86 and the second zone 88 arepreferably disposed transversely inwardly from the outer longitudinaledges 84 of the backing substrate 52. (As used herein, the term"transversely inwardly" means toward the longitudinal centerline L. Theterm "transversely outwardly" means away from the longitudinalcenterline L.) The area between the outer longitudinal edges 84 of thebacking substrate 52 and the zones 86 and 88 of pressure-sensitiveadhesive 54 creates fixed regions 74 and 76. These fixed regions 74 and76 are preferably greater than or equal to about 0.5 mm, to aid inprocessability and cleanliness of the process.

The first zone 86 and the second zone 88 are also preferablytransversely separated about the longitudinal centerline L. This leavesa nonadhesive area 75, preferably greater than or equal to about 0.5 mm,between the first zone 86 and the second zone 88 that can be used as arelease tab 85. The non-adhesive area 75, also aids in processability byaiding the slitting operation 134. The release tab 85, as shown in FIGS.5 and 7 provides the user with a portion of the backing substrate 52which is free of pressure-sensitive adhesive 54 and preferably notadhered to the release substrate or any other element of the diaper 20.Thus, the user may grasp the release tab 85 and more easily open thetape tab 40. (As used herein, the term "open the tape tab" refers toseparating the pressure sensitive adhesive 54 disposed on the tape tab40 from the release substrate 50 or any other surface to which thepressure-sensitive adhesive 54 may be adhered.) However, if the firstzone 86 and the second zone 88 are not transversely separated about thelongitudinal centerline L, alternative methods of providing a releasetab 85 are available. The methods include, but are not limited to,folding a portion of the backing substrate 52 adjacent the innerlongitudinal edges 83 onto the pressure-sensitive adhesive 54 disposedon the backing substrate 52 (shown in FIG. 5), or coating the backingsubstrate 52 adjacent the inner longitudinal edges 83 with a releaseagent or any other material that will prevent the pressure-sensitiveadhesive 54 in the area adjacent the inner longitudinal edges 83 fromadhering to the release substrate 50 or any other elements of the diaper20.

As shown in FIG. 3c, the backing substrate 52 is preferably slit alongthe longitudinal centerline L, forming two backing substrate segments,90 and 92. (Embodiments are contemplated, however, wherein more than twozones of pressure-sensitive adhesive 54 are applied to the backingsubstrate 52 and wherein the backing substrate 52 is slit and separatedinto more than two backing segments.) The backing substrate segments, 90and 92, are preferably separated transversely before they are broughtinto contact with the release substrate 50 (shown in FIG. 3d).

The release substrate 50 has a release surface 94 and an adhesivesurface 96 opposed the release surface 94. The release surface 94 ispreferably comprises a release agent as described above, and is placedin contact with the pressure-sensitive adhesive 54 disposed on the firstsurface 80 of backing substrate segments 90 and 92. In a preferredembodiment, as shown in FIG. 3d, the release substrate 50 at leastpartially covers both the first zone 86 and the second zone 88 ofpressure-sensitive adhesive 54; the first zone 86 being disposed onsegment 90 and the second zone 88 being disposed on the segment 92 ofthe separated backing substrate 52.

Once the release surface 94 of the release substrate 50 contacts thezones 90 and 92 of pressure-sensitive adhesive 54, the segments 90 and92 of the backing substrate 52 become releasably joined to the releasesubstrate 50, forming a laminate 60. The laminate 60, as shown in FIG.3e, has an outer surface 62, an adhesive surface 64, a longitudinalcenterline L1 and a transverse centerline T1. The adhesive surface 64 ofthe laminate 60 comprises the adhesive surface 96 of the releasesubstrate 50. As shown in FIG. 2, the laminate 60 is preferably passedadjacent a spray nozzle 150 that applies a construction adhesive 56 tothe adhesive surface of the release substrate 50. The constructionadhesive 56 may be applied to the entire adhesive surface 96 of therelease substrate 50. In a preferred embodiment, as shown in FIG. 3e,however, the construction adhesive 56 is applied laterally inwardly fromthe side edges 100 of the release substrate 50 at least about 0.5 mm toensure the cleanliness of the process. (As noted above, the adhesive maybe applied continuously or in any pattern. Alternatively, theconstruction adhesive 56 may be applied at least about 0.5 mm from thelongitudinal edges 84 of the backing substrate 52.) In another preferredembodiment, the construction adhesive applied in transversely separatedzones such that an adhesive free area 101 is present preferably parallelto and juxtaposed or coincident with the longitudinal centerline L1. Theadhesive free area 101 is preferably greater than or equal to about 0.5mm to aid in the slitting operation that takes place at shear slitter160. The construction adhesive 56 preferably comprises a permanent, hotmelt adhesive as described above.

After the construction adhesive 56 is applied to the adhesive surface 96of the release substrate 50, the laminate 60 is preferably slit alongits longitudinal centerline L1 and separated to form tape tab stock 70,as shown in FIG. 3f. The tape tab stock 70 has a longitudinal centerlineL2, a transverse centerline T2 perpendicular to the longitudinalcenterline L2, an adhesive surface 102 and a non-adhesive surface 104.The tape tab stock 70 is preferably fed directly into the taper unit 170that can be integrated into the absorbent article manufacturing line.The taper unit 170 cuts the tape tab stock 70 in a direction parallel tothe transverse centerline T2 to form the individual tape tabs 40. Thetaper unit 170 then joins the adhesive surface 102 of the tape tabs 40to individual absorbent articles manufactured concurrently with the tapetabs 40.

b. One-piece tape tab

In another preferred embodiment of the one-piece tape tab, as shown inFIG. 7, the tape tab 40 is joined to the chassis of the absorbentarticle with a permanent construction adhesive as described above withregard to the two-piece tape tab. In is this embodiment, the stepsdescribed above relating to the preparation of a backing substrate 52comprising zones 86 and 88 of pressure-sensitive adhesive 54 arefollowed. As shown in FIG. 6, the pressure-sensitive adhesive 54 ispreferably applied in zones that are transversely separated about thelongitudinal centerline L3 such that the width between the zones isgreater than or equal to about 0.5 mm. However, before the backingsubstrate 52 is slit and separated, a construction adhesive 56 isapplied to the second surface 82 of the backing substrate 52.Preferably, the construction adhesive 56 is applied continuously to thebacking substrate 52 in zones, rather than to the entire second surface82 of the backing substrate 52. The zones of construction adhesive 56are preferably transversely separated about the longitudinal centerlineL3. Further, as shown in FIG. 6, the zones of construction adhesive 56are preferably disposed transversely inwardly or transversely outwardlyfrom the zones of pressure-sensitive adhesive 54 and preferably disposedinwardly from edge 84 greater than or equal to about 0.5 mm. Thisensures that at least a portion of the backing substrate 52 comprisingthe pressure-sensitive adhesive 54 can be folded over the first surface80 of the backing substrate 52 to form a tape tab 40 once the backingsubstrate 52 is slit into segments.

The backing substrate 52 is preferably slit along the longitudinalcenterline L3 and separated, forming at least two backing substratesegments as described above. These backing substrate segments are feddirectly into a taper unit 170 which cuts the backing substrate segmentsinto individual tape tabs 40. Each individual tape tab has a fixed end77 and a releasable end 78. The releasable end 78 preferably comprisesthe pressure-sensitive adhesive 54 applied to the substrate backing 52.(In especially preferred embodiments, the releasable end comprises arelease tab 85 as described above.) The fixed end 77 preferablycomprises the construction adhesive 56 disposed on the second surface 82and a release surface 95. The release surface 95 may comprise anyrelease agent known in the art, including but not limited to, silicone,wax, or clay; or the release surface 95 may be formed by impregnatingpredetermined portions of the backing substrate 52 with a release agent,or by embossing or bonding the backing substrate 52 such that a releasesurface 95 is formed. Alternatively, a backing substrate 52 may bechosen that comprises areas of differing molecular structures, such aslaminates or coextruded films, wherein at least a portion of the firstsurface 80 of the backing substrate 52 acts as a release surface 95.

Finally, the tape tab stock 70 is fed into a standard taper unit as iscommonly known in the art. One such unit, as supplied by Curt G. Joa,Inc. of Sheboygan Falls, Wis., feeds the tape tab stock 70 to an anvilroll where the tape tab stock 70 is cut into individual tape tabs 40.The individual tape tabs 40 are then slipped (spaced) and the fixed end77 of each tape tab 40 is joined to the chassis of the absorbent articleby means of the construction adhesive 56 disposed on the second surface82 of the backing substrate 52.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A method for manufacturing tape tab stock thatmay be used to form tape tabs for use with a disposable absorbentarticle, the method comprising the steps of:providing a backingsubstrate having a longitudinal centerline, a transverse centerlineperpendicular to said longitudinal centerline, a first surface, and apair of longitudinal edges; applying a pressure-sensitive adhesive tosaid first surface of said backing substrate, said adhesive beingapplied in at least a first zone and a second zone, said first andsecond zones being transversely spaced apart and running continuously ina direction parallel to said longitudinal centerline of said backingsubstrate, said first and second zones being located on opposite sidesof said longitudinal centerline and between said longitudinal centerlineand said longitudinal edges wherein said first and second zones arespaced transversely inwardly toward said longitudinal centerline fromsaid longitudinal edges at least about 0.5 mm such that an area formedadjacent to each of said longitudinal edges is free of saidpressure-sensitive adhesive; slitting said backing substrate betweensaid first zone and said second zone, parallel to said longitudinalcenterline to form at least two segments, each said segment having aninner longitudinal edge; separating said segments in a directionparallel to said transverse centerline; contacting a release substrate,having a release surface, an adhesive surface and a pair of side edges,with said pressure-sensitive adhesive, such that said release surface atleast partially covers said pressure-sensitive adhesive located in bothsaid first zone and said second zone forming a unitary laminatecomprising said segments and said release substrate; applying aconstruction adhesive to at least a portion of said adhesive surface ofsaid release substrate; slitting said laminate between said segments ina direction parallel to said longitudinal centerline; and separatingsaid laminate into a tape tab stock.
 2. The method of claim 1 whereinsaid construction adhesive is applied at least about 0.5 mm from saidlongitudinal edges of said backing substrate.
 3. The method of claim 1wherein said construction adhesive is applied at least about 0.5 mm fromsaid side edges of said release substrate.
 4. The method of claim 1wherein said step of slitting said backing substrate comprises slittingsaid backing substrate coincident with said longitudinal centerline. 5.The method of claim 1 wherein said construction adhesive comprises apressure-sensitive adhesive.
 6. The method of claim 1 wherein saidpressure-sensitive adhesive comprises a cohesive adhesive.
 7. The methodof claim 1 further comprising the steps of:cutting said tape tab stockinto individual tape tabs, each having a permanently attached end and anrefastenable end; providing a chassis of an absorbent article; andsecuring said permanently attached end of said tape tab to said chassiswith said construction adhesive.
 8. The method of claim 7 furthercomprising the step of folding said inner longitudinal edges back ontosaid first surface of said backing substrate to form release tabs, saidfolding step being performed before said release substrate is placed incontact with said backing substrate.
 9. A method for manufacturing tapetab stock that may be used to form tape tabs for use with a disposableabsorbent article, the method comprising the steps of:providing abacking substrate having a first longitudinal centerline, a transversecenterline perpendicular to said first longitudinal centerline, a firstsurface, and a pair of longitudinal edges; applying a pressure-sensitiveadhesive to said first surface of said backing substrate, said adhesivebeing applied in at least a first zone and a second zone, said first andsecond zones being transversely spaced apart and running continuously ina direction parallel to said first longitudinal centerline of saidbacking substrate, said first and second zones being located on oppositesides of said longitudinal centerline and between said firstlongitudinal centerline and said longitudinal edges wherein said firstand second zones are spaced transversely inwardly toward saidlongitudinal centerline from said longitudinal edges at least about 0.5mm such that an area formed adjacent to each of said longitudinal edgesis free of said pressure-sensitive adhesive; slitting said backingsubstrate between said first zone and said second zone, parallel to saidfirst longitudinal centerline to form at least two segments, each saidsegment having an inner longitudinal edge; separating said segments in adirection parallel to said transverse centerline; contacting a releasesubstrate, having a release surface, an adhesive surface and a pair ofside edges, with said pressure-sensitive adhesive, such that saidrelease surface covers said pressure-sensitive adhesive located in bothsaid first zone and said second zone forming a unitary laminatecomprising said segments and said release substrate, said laminatehaving a second longitudinal centerline; applying a constructionadhesive to at least a portion of said adhesive surface of said releasesubstrate, said construction adhesive applied in zones that aretransversely spaced apart about said second longitudinal centerlineforming an area free of construction adhesive such that said area freeof construction adhesive between said zones is greater than or equal toabout 0.5 mm; slitting said laminate between said segments in adirection parallel to said longitudinal centerline; and separating saidlaminate into a tape tab stock.
 10. The method of claim 9 wherein saidconstruction adhesive is applied at least about 0.5 mm from saidlongitudinal edges of said backing substrate.
 11. The method of claim 9wherein said construction adhesive is applied at least about 0.5 mm fromsaid side edges of said release substrate.
 12. The method of claim 9wherein said first and second zones are transversely separated at leastabout 0.5 mm, forming a pressure-sensitive adhesive free area about saidfirst longitudinal centerline.
 13. The method of claim 12 wherein saidstep of slitting said backing substrate comprises slitting said backingsubstrate coincident with said first longitudinal centerline such that aslit is made within said pressure-sensitive adhesive free area.
 14. Themethod of claim 13 wherein said step of slitting said laminate comprisesslitting said laminate coincident with said second longitudinalcenterline such that a slit is made within said area free ofconstruction adhesive.
 15. The method of claim 14 further comprising thesteps of:cutting said tape tab stock into individual tape tabs, eachhaving a permanently attached end and an refastenable end; providing achassis of an absorbent article; and securing said permanently attachedend of said tape tab to said chassis with said construction adhesive.16. The method of claim 15 further comprising the step of folding saidinner longitudinal edges back onto said first surface of said backingsubstrate to form release tabs, said folding step being performed beforesaid release substrate is placed in contact with said backing substrate.17. The method of claim 9 wherein said construction adhesive comprises apressure-sensitive adhesive.
 18. The method of claim 9 wherein saidpressure-sensitive adhesive comprises a cohesive adhesive.